Ludwig van Beethoven, Brief an Georg Friedrich Treitschke, Wien, Anfang März 1814, Autograph

Beethoven thanks the head of the theatre and director Treitschke for his advantageous work on the libretto for "Fidelio" op. 72. However he will not be able to rework the music for the opera in two weeks due to lack of time, "it would be quicker to write something new, rather than composing something new to be added to the old". "The score of the opera is written in such a terrible hand […] In short I assure you, dear T., that the opera will give me the martyr's crown". Beethoven asks for the planned performance to be postponed. In 1814 Beethoven decided to completely revise his opera Fidelio once again. The reason for this was the revival of the opera for the benefit of the singers Saal, Vogl and Weinmüller at the royal court opera. They had asked for Fidelio for their benefit performance

Beethoven had already once revised his opera of 1805 in 1806 but was still not happy with the work and made a new revision a condition for the singers. With the permission of the librettist of the first version, Joseph Sonnleithner, the experienced man of the theatre Treitschke was commissioned to undertake a fundamental revision of the text.